Name Introduction to Chemistry Reviewing Vocabulary Match the definition to Column A with the term in Colum B. Column A Date Class Column B 1. A systematic approach used in all scientific study 2. Anything that takes up space and has mass 3. A chemical that protects organisms from UV radiation 4. Any substance with a definite composition 5. A visual, verbal, or mathematical explanation of how things occur 6. The study of matter and the changes it undergoes 7. The act of gathering information 8. A judgment based on the information obtained a. Chemical b. Chlorofluorocarbon c. Model d. Matter e. Ozone f. Scientific method g. Conclusion h. Technology i. Chemistry j. Observation during an experiment 9. The practical use of scientific research 10. A chemical made up of chlorine, fluorine, and carbon Compare and contrast each pair of related terms. 11. qualitative data, quantitative data
12. hypothesis, theory 13. dependent variable, independent variable Circle the letter of the choice that best completes the statement 14. A constant is a factor that a. changes during an experiment c. is affect by the dependent variable b. changes from one lab group to another d. is not allowed to change during an experiment 15. A control is a. variable that changes during an experiment c. type of dependent variable b. standard for comparison d. type of experiment 16. A hypothesis is a(n) a. set of controlled observations c. tentative explanation of observations b. explanation supported by many experiments d. law describing a relationship in nature 17. A theory is a(n) a. set of controlled observations c. tentative explanation of observations b. explanation supported by many experiments d. law describing a relationship in nature
18. A model is a(n) a. visual, verbal, and/or mathematical explanations of how things occur b. explanation that is supported by many experiments c. description of a relationships in nature d. tentative explanation about what has been observed In the space at the left, write the word or phrase in parentheses that correctly completes the statement. 19. Molina and Rowland used a (model, scientific method) to learn about CFCs in the atmosphere. 20. Their hypothesis was that CFCs break down in the stratosphere due to the interactions with (ultraviolet light, oxygen). 21. Molina and Rowland thought that these interactions produced a chemical that could break down (chlorine, ozone). 22. To test their (data, hypothesis), Molina and Rowland examined interactions that occur in the stratosphere. 23. Based on their data, Molina and Rowland developed a (hypothesis, model) that explained how CFCs destroy ozone. 24. Molina and Rowland concluded that (chlorine, radiation) formed by the breakdown of CFCs in the stratosphere reacts with ozone and destroys it.
Understanding Main Ideas (Part B) Identify each piece of data as either qualitative or quantitative 1. Red 2. 100 pounds 3. 105 C 4. Tall 5. Round 6. Smells like bananas 7. 40 mph 8. Pink with purple polka dots 9. Cold 10. 78 books Scientific notation and dimensional analysis 1. Circle the figures that are written in correct scientific notation. 1.61 * 10 2 kg 1.61 * 10 * 10m 1.61 * 100 m 161 km 1.627 62 * 10-27 kg 9.109 39 * 10-31 nm 2.8 * 10-8 1 380 000 2. Change the following data into scientific notation. a. 5 000 000km c. 0.000 421 g b. 8 394 000 000 s d. 0.03 cm Complete the following dimensional analysis problems. 3. Convert 50 kilograms to grams.
4. Convert 5 meters into centimeters. 5. Convert 5 liters into kiloliters. 6. Convert 5 centimeters into meters. 7. Convert 55 kilograms per hour into meters per second. Use each of the terms below just once to complete the statements Counting numbers Estimated Non-zero Zeros Scientific notation Significant figures placeholders 8. The digits that are reported in an answer are called. 9. The numeral 9.66 has three significant figures, two known figures and one figure. 10. numbers are always significant. 11. All final to the right of the decimal place are significant. 12. Zeros that act as are not significant. 13. have an infinite number of significant figures. 14. When you convert to, you remove the placeholder zeros. 15. Round the following to four significant figures. a. 12.555 km c. 99.999 b. 1.0009 d. 23.342 999
16. Round 12.783 456 to the requested number of significant figures. a. 2 significant figures c. 6 significant figures b. 5 significant figures d. 7 significant figures 17. Round 120.752 416 to the requested number of significant figures. a. 3 significant figures c. 5 significant figures b. 4 significant figures d. 7 significant figures 18. Complete the following calculations. Round off the answers to the correct number of significant figures. a. 51.2 kg + 64.44 kg b. 6.435 cm 2.18 cm c. 16 m x 2.82 m x 0.05 m d. 3.46m / 1.82 s Applying Scientific Methods A chemistry student is given the task of analyzing three unknown samples. Her data is listed in Data Table 1. Use Data Table 1 to answer the questions below. Data Table 1 Sample A Sample B Sample C Trial Mass (in grams) Volume (in ml) Mass (in grams) Volume (in ml) Mass (in grams) Volume (in ml) 1 80.72 10.01 95.41 10.72 72.28 10.00 2 80.64 10.00 92.33 10.51 72.32 9.99 3 80.91 10.05 93.78 10.62 72.34 9.95 Avg 80.76 10.02 93.84 10.62 72.30 9.98
19. Based on the data given, what is the density of each sample? Follow the rules for significant figures and rounding for your answers. Sample A Sample B Sample C 20. Compare the data for each trail and each sample in Data Table 1. Which sample(s) did the student measure precisely? Explain your answer. 21. The student compares her data to the following chart in the back of her textbook. Can she identify Sample A, B, and C based on the data she recorded? Table A Properties of Common Metals Name Color at room temperature Density (g/cm 3 ) Aluminum Silver metal 2.701 Copper Red metal 8.92 Iron Silver metal 7.86 Nickel Silver metal 8.90 Tin White metal 7.28
22. What information would you suggest the student obtain so that she can more accurately identify the samples? 23. Assume that Sample A is copper, Sample B is nickel and Sample C is tin. What is the percent error for each one? For the following problem, you must use Unit Cancellation/Dimensional Analysis to receive credit. 24. Mr. Karbon is 35 years old and his heart beats on average 62 beats per minute. How many times has his heart been beating during his life? (assume there are no leap years)